Accurate measuring, marking, and cutting of fabric is important for many applications, including upholstery of furniture and the fabrication of garments, draperies linens and quilts. Factors which need to be considered include the grain of the fabric (lines parallel to the selvedge being referred to as lengthwise straight of grain, and lines at right angles to the selvedge being referred to as crosswise straight of grain), and, in appropriate fabrics, the position and repeat of decorative patterns, and the up-down direction, particularly the nap direction.
Modern garment cutting patterns are generally supplied with instructions, e.g. directional arrows on the pattern, how the cutting pattern should be positioned on the fabric, for example relative to the straight of grain. In present practice, in order to identify the straight of grain at any point on a conventional fabric, one must either reference the selvedge, and measure and mark the straight of grain at that point, or, if there is no selvedge, find another way of determining the straight-of-grain. Identification of other fabric characteristics, e.g. a nap or lay direction, or the position and repeat of a decorative pattern, similarly requires careful and repetitive work. As a result, a significant percentage of sewn items arrive on the market with visible problems resulting from failure to correctly account for fabric characteristics such as grain, nap, decorative pattern and repeat of decorative pattern.
U.S. Pat. Nos. 4,869,726 (Linda et al) and 6,839,971 (Schafer et al) describe attempts to mitigate the problems outlined above.